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%I #7 May 01 2013 21:11:53
%S 1,10,105,1180,14143,158036,1703161,17520558,157563619,1431557207
%N Number of primes p in the range 9 < p <= prime(10^n) that begin and end with the same digit.
%F a(n) = A145709(n) + A145710(n) + A145711(n) + A145712(n). [R. J. Mathar, Aug 02 2010]
%e The initial 1 is from the prime 11.
%e a(4)=1180 because to 10^4 or 10000 primes, ending in 104729=A006988(4), there are 1180 primes with equal and distinct first and last digits: 1 and 1, 3 and 3, 7 and 7 and 9 and 9.
%Y Cf. A145709 - A145712
%K hard,more,nonn,base
%O 1,2
%A _Enoch Haga_, Oct 16 2008
%E Edited by _N. J. A. Sloane_, Aug 16 2010
%E a(6) corrected and a(7)-a(10) added by _D. S. McNeil_, Aug 29 2010
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